Open end spinning apparatus



Dec. 2, 1969 J' M, SHEPHERD ET AL 3,481,129

i v OPEN END SPINNING APPARATUS Filed Nov. 7, 196'? l gNvEN'ro I x QMJM ATTORNEY 5 United States Patent O 3,481,129 OPEN END SPINNING APPARATUS John M. Shepherd, Ramsbottom, near Bury, Christopher .1. Copple, Blackburn, and David Tattersall, Accrington, England, assignors to T.M.M. (Research) Limited, Oldham, Lancashire, England, a British company Filed Nov. 7, 1967, Ser. No. 681,239 Claims priority, application Great Britain, Nov. 8, 1966,

0,030/ 66 Int. Cl. D01h 7/00, 1/12 U.S. Cl. 57-58.89 7 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to open end or break spinning of textile yarns in which a twisted yarn is formed by continuously depositing discrete fibres on a rotating collecting surface, continuously removing them from the surface to form the tail end of a yarn with respect to which the surface rotates and drawing off the continuously formed twisted yarn.

In open end spinning apparatus which has hitherto been proposed discrete fibres are fed in an airstream into a rotating spinning chamber and deposited on an inner surface of the chamber, from which they are picked up by a tail end of yarn which is continuously withdrawn from the top or bottom of the chamber. Air is permitted to escape from the chamber through holes provided in the chamber near the region at which the fibres are deposited or at other -positions in the spinning chamber. The holes provided for the escape of air are however of small size and easily become blocked with fibre or extraneous matter and require frequent cleaning.

It is an object of the present invention to provide an open-end spinning apparatus which does not suffer from this disadvantage.

According to the present invention, there is provided apparatus for the open-end spinning of textile yarns cornprising a spinning rotor to which fibres are fed in an airstream, said spinning rotor being closed at one end and open at the other end and having a wall extending between the open and closed ends to provide a fibre collecting surface', said wall being free from perforations or apertures.

In a preferred embodiment of the invention the openend of the rotor is covered by a stationarily arranged cover member, and a fibre feed tube delivering discrete fibres to the rotor and a yarn delivery tube through which the formed yarn leaves the rotor passes through the stationary cover member. An annular clearance is provided between the cover member and the open end of the rotor to permit the escape of air from the interior of the rotor and the rotor is rotatably mounted within a housing including duct means for connecting the interior of the housing to suction means, whereby air is drawn into the interior of the rotor through the yarn delivery tube and the fibre feed tube, from the interior of the rotor into the housing through the clearance between the open end of the rotor and the cover member and from the housing through said duct means.

HCC

One embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which:

FIG. 1 is a sectional side elevation of open end spinning apparatus according to an embodiment of the invention, and

FIG. 2 is an underside view of the top cover plate for the rotor housing in the apparatus shown in FIG. 1.

Referring to the drawings, a spinning rotor 11 is fxedly mounted on the upper end of a drive shaft 12 rotatably supported in bearings 13 and 14 mounted in a rotor housing 15 which is in turn mounted in a bracket 16 forming part of the machine frame. The rotor housing 15 can be turned within the bracket 16 about an axis parallel to but offset from the rotor drive shaft 12 so that the unit formed by the housing and the rotor can be brought from an operative position, as shown in FIG. l, in which the drive shaft 12 is drivably engaged by a friction driving belt 17 held by a jockey pulley 18 to an inoperative position in which the drive shaft 12 is out of engagement with the belt 17. The rotor 11 is of shallow dished configuration and has a substantially fiat circular base portion 19, an upwardly and outwardly extending frusto-conical lower wall portion 20 integral with the base portion 19, a radially outwardly directed circumferential groove 21 forming a fibre collecting inner surface and an upwardly and inwardly extending frusto-conical lip portion 22.

The rotor housing 15 is provided with a removable cover plate 23 the lower surface of which is stepped to form a central cylindrical depending portion 24 which extends downwardly just into the upper open end of the rotor 11, leaving a small annular clearance between it and the terminal lip portion 22 of the rotor. The cover plate 23 is formed with a central opening which is fitted with a vertically arranged yarn delivery tube 25 through which the formed yarn 26 from the rotor is continuously passed upwardly and out of the rotor housing 15. The yarn delivery tube 25 extends as shown just below the cylindrical depending portion 24 of the cover plate 23.

The cover plate 23 is formed to receive a fibre feed tube 27 which passes through it and terminates at a position close to the fibre collecting surface of the rotor 11. The disposition of the feed tube 27 is such that fibres are delivered by it substantially tangentially to the fibre collecting surface of the rotor 11 and in the present embodiment of the invention the feed tube 27 is arranged to taper gradually to its exit end while the inlet end of the tube is cut so that it can be' located close to the nip point of a pair of delivery rollers 28, 29 forming part of a high-draft roller-drafting system 30 to which a silver 31 is fed.

In operation, the rotor housing 15 is maintained at sub-atmospheric pressure by a suction pump (not shown) connected to a suction pipe 32 communicating with the interior of the housing through a port 33. As a result, air from the atmosphere is drawn into the housing 15 through the feed tube 27 and through the yarn delivery tube 25. Fibres in discrete form are presented to the feed tube 27 by the front rollers 28, 29 of the drafting system and are propelled in the airstream through the tube 27 and delivered to the fibre collecting surface of the rotor 11, which is arranged to rotate at very high speed in excess of 15,000 r.p.m. under the drive from the roller 18. The fibres fed to the rotor 11 are deposited on the fibre collecting surface by the action of centrifugal force and collect in the groove 21. The fibre conveying airstream loses its velocity by expansion in the interior of the rotor 11, the air escaping through the clearance between the rotor lip 22 and the depending portion 24 of the cover plate 23 and entering the housing 15 from which it is withdrawn through port 33 and pipe 32 by the suction pump. The fibres deposited in the libre collecting groove 21 of the rotor are picked up and twisted into a tail end of yarn in well known manner and the formed yarn 26 is continuously withdrawn through the yarn delivery tube 25.

During spinning, the bore of the yarn delivery tube 25 is restricted by the yarn 26 being delivered and the major portion of the air drawn into the rotor 11 passes through the feed tube 27. The airstream passing through the yarn delivery tube 25 is however employed to assist in the passing of a seed yarn into the rotor 11 when starting up the machine or when piecing up following and end break.

During the normal operation of the machine, the tail end of yarn 26 takes up substantially all fibres fed to the rotor 11 but there are occasions when an excessive 'build up of fibres occurs in the interi-or of the rotor 11, for instance when an end breaks and the feed of fibres is continued before the stop motion controlling the feed operates. It is of course desirable to remove any excess of fibres without removing the cover plate 23 and for this purpose the underside of the cover plate 23 including the depending cylindrical portion 24 is cut away, as shown, to form a wide radial recess 34 extending inwardly beyond the periphery of the lip portion 22 ofthe rotor 11. By maintaining the airstream into the rotor 11 through the feed tube 27 and the yarn delivery tube 25 whilst reducing the speed of the rotor 11 until the fibres are no longer held on the inner surface of the rotor 11 by centrifugal force, the bundle of unwanted fibres is withdrawn under suction from the rotor 11 along the radial recess 34 in the cover plate 23 and into the rotor housing from which it is withdrawn by the suction pump.

Whilst the embodiment hereinbefore described includes a rotor 11 having a substantially fiat `base portion with wall and lip portions, other configurations having substantially concave or convex base portions and other forms of lip portion may if desired by employed.

What we claim as our invention and desire to secure by Letters Patent is:

1. Apparatus for the open end spinning of textile yarns comprising a spinning rotor to which fibres are fed in an airstream, said spinning rotor being closed at one end and open at the other end and having a wall extending between the open and closed ends to provide a L fibre collecting surface, said wall being free from perforations or apertures, a cover member for the open end of said rotor, a fibre feed tube passing through said cover and delivering discrete fibres to said rotor, and a yarn delivery tube passing through said cover and in which formed yarn leaves the rotor through said cover member, said cover being spaced from the adjacent wall of the rotor to form a clearance therebetwen thereby permitting the escape of air from the interior of said rotor.

2. Apparatus according to claim 1, wherein the rotor is rotatably mounted within a housing and wherein the housing includes duct means for connecting the interior of the housing to suction means, whereby air is drawn into the interior of the rotor through the yarn delivery tube and the fibre feed tube, from the interior of the rotor into the housing through the clearance between the open end of the rotor and the cover member and from the housing through said duct means.

3. Apparatus according to claim 2, wherein the cover member includes an inner depending cylindrical portion which extends into the open end of the rotor, leaving said clearance between it and the rotor for the passage of air from the rotor to the housing.

4. Apparatus according to claim 3, wherein the depending cylindrical portion of the cover is cut away to form a single passage for the removal of unwanted fibres from the rotor, the arrangement being such that by cutting off the supply of fibres to the rotor while maintaining the withdrawal of air from the rotor by the action of said suction means and reducing the speed of: the rotor the fibres remaining in the rotor become no longer held in the rotor by centrifugal force and are withdrawn from the rotor through the single passage in the cover member and into the rotor housing and from the housing into the duct means.

5. Apparatus according to claim 1, wherein the bore of the yarn delivery tube is so restricted that when yarn is being delivered therethrough the major portion of the air drawn into the rotor passes through the fibre feed tube.

6. Apparatus according to claim 1, wherein the fibre fed tube reduces gradually in cross-section in the direction of the feed of bres therethrough.

7. Apparatus according to claim 1, wherein the cover member is formed with a central opening within which is fitted the yarn delivery tube through which the formed yarn from the rotor is continuously withdrawn, and wherein the fibre feed tube passes through the cover and terminates in a position close to the bre collecting surface of the rotor, the disposition of the feed tube being such that fibres are delivered by it substantially tangentially to the fibre collecting surface of the rotor.

References Cited UNITED STATES PATENTS 3,119,223 1/ 1964 Meimberg 57-58.95 XR 3,163,976 1/1965 Juillard 57-58.89 3,328,949 7/1967 Pavek et al. 57-58.89 3,335,558 8/1967 Doudlebsky et a1. 57--5895 3,370,413 2/1968 Rajnoha et al. 57-58.95

JOHN PETRAK'ES, Primary Examiner U.S. C1. X.R. 57-58.91, 58.95 

